1. Field of the Invention
The present invention relates to a guide apparatus (guide tool) which is adapted to insert and screw-engage an implant between adjacent corpus vertebrae to cure a degenerative disease of a corpus vertebra such as a cervical vertebra.
2. Description of the Related Art
In order to cure the degenerative disease called cervical vertebra, in a known operation, a screw (implant) is screw-engaged in a subluxation portion between an atlas (first cervical vertebra) and a second cervical vertebra. However, in this operation, there is a possibility that the spinal cord or nerve root which exists very close to the screw-engaging portion may be injured during the operation. To avoid this, the operation requires a long time, thus resulting in a heavy burden on a doctor as well as a patient.